St. Petersburg police say they are investigating a “suspicious” house fire that killed an 18-year-old girl on Coquina Key over the weekend.

The fire was reported about 3:30 a.m. Sunday at a single-story home in the 3900 block of Neptune Drive Southeast, according to the police department.

Four people were inside the home at the time of the fire. Angelina Anderson, 18, died of her injuries. A 35-year-old woman was hospitalized in critical but stable condition. Two children were treated at a hospital for smoke inhalation and later released.

St. Petersburg police say the cause of the fire is suspicious and remains under investigation. No further information was released.